Magas was a royal prince of the Ptolemaic Dynasty. He was the son of Ptolemy III Euergetes I (246-221 B.C.E.) and Queen Berenice III. Magas did not inherit the throne, which went to Ptolemy IV Philopator (221-205 B.C.E.). The prince was reportedly brutally murdered by Ptolemy IV as a result of being suspected of treason. Their mother, Queen Berenice, and an uncle passed in the same royal purge.